Only Comment - Myanmar Standards

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DMMS NIOSH 6015: 1994

& 6016: 2016

Method for sampling and determination

of ammonia

MYANMAR STANDARD (Draft)

NIOSH 1994

NIOSH 2016

DRI 2019

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AMMONIA 6015

NH3 MW: 17.03 CAS: 7664-41-7 RTECS: BO0875000

METHOD: 6015, Issue 2 EVALUATION: PARTIAL Issue 1: 15 August 1994

OSHA : 50 ppmNIOSH: 25 ppm; STEL 35 ppm; Group III pesticideACGIH: 25 ppm; STEL 35 ppm

(1 ppm = 0.697 mg/m 3 @ NTP)

PROPERTIES: gas; MP -77.7 °C; BP -33.4 °C; explosive range 16 to 25% v/v in air; vapor density 0.6 (air = 1)

SYNONYMS: none

SAMPLING

SAMPLER: SOLID SORBENT TUBE(sulfuric acid-treated silica gel)A 0.8-micron MCE prefilter may be used toremove particulate interferences.

FLOW RATE: 0.1 to 0.2 L/min

VOL-MIN: 0.1 L @ 50 ppm -MAX: 96 L

SHIPMENT: routine

SAMPLE STABILITY: not determined

BLANKS: 2 to 10 field blanks per set

MEASUREMENT

TECHNIQUE: VISIBLE ABSORPTIONSPECTROPHOTOMETRY

ANALYTE: indophenol blue

EXTRACTION: 20 mL deionized water

COLOR DEVELOPMENT: EDTA antiprecipitant, phenolate coupling

agent, n i t roprusside intensi f ier ,hypochlorite.

WAVELENGTH: 630 or 660 nm

CALIBRATION: standard solutions of ammonium chloridein deionized water

RANGE: 1.5 to 20 µg per sample [1]

ESTIMATED LOD: 0.5 µg per sample [1]

PRECISION (S r): not determined

ACCURACY

RANGE STUDIED: not studied

ACCURACY: not determined

BIAS: not determined

OVERALL PRECISION (S rT): not determined

APPLICABILITY: The working range is 0.2 to 400 ppm (0.15 to 300 mg/m 3) for a 10-L air sample. This method is applicableto STEL measurements.

INTERFERENCES: None identified.

OTHER METHODS: This method is based on the sampling procedure of Method S347 [2], the automated analytical procedureof EPA Method 350.1 [3], and Standard Methods 417G [4]. NIOSH Method 6701 [5] was less sensitive, employing a passive li quidsorbent badge for collection followed by ion chromatography. NIOSH Method P&CAM 205 [6] used impinger collection andNessler's reagent for manual colorimetric analysis. OSHA has both impinger collection with ion specific electrode analys is (ID-164)[7] and sulfuric acid-impregnated beaded carbon collection followed by ion chromatography analysis (ID-188) [8].

NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 8/15/94

MYANMAR STANDARD (Draft) DMMS NIOSH 6015: 1994

© NIOSH 1994 - All rights reserved ©DRI 2019 - All rights reserved

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AMMONIA: METHOD 6015, Issue 2, dated 15 August 1994 - Page 2 of 7

REAGENTS:

1. Water, distilled and deionized. Specialprecaution must be taken to ensure thatdistilled water is free of ammonia, by passingit through an ion exchange column comprisedof a mixture of both strongly acidic cation andstrongly basic anion exchange resins.Regenerate the ion exchange columnaccording to the instructions of themanufacturer.NOTE: All solutions must be made using

ammonia-free water. 2. Sulfuric acid, conc., reagent grade. 3. Phenol. 4. Sodium hydroxide, reagent grade. 5. Brij-35. 6. Ammonium chloride. 7. Chloroform. 8. Sulfuric acid 5 N. Air scrubber solution (AAII).

Carefully add 140 mL of concentrated sulfuricacid to approximately 500 mL of ammonia-freedistilled water. Cool to room temperature anddilute to 1 L with ammonia-free water.

9. Sodium phenolate. In a 1-liter flask, dissolve83 g phenol (or 80 mL 90% liquid phenol) in500 mL distilled water. In small increments,cautiously add with agitation, 32 g NaOH (96g 50% NaOH for TRAACS). Periodically coolflask under water faucet. When cool, dilute to1 L with distilled water. Filter if necessary.Store in amber glass bottle. For AAII add 0.5mL Brij-35.

10. Sodium hypochlorite solution: Dilute onevolume of a bleach solution containing 5.25%NaOCl (such as "Clorox") with an equalvolume of deionized water. Available chlorinelevel should approximate 2 to 3%.

11. Disodium ethylenediamine-tetraacetate(EDTA) (5%): Dissolve 50 g EDTA (disodiumsalt) and six pellets NaOH in 1 L of deionizedwater. (For TRAACS, dissolve 41 g EDTA, 1g 50% NaOH, and 3-6 mL Brij-35.)

12. Sodium nitroprusside (0.05% Na 2Fe(CN)5NO· 2H2O): Dissolve 0.5 g sodium nitroprussidein 1 L deionized water (or 1.1 g for TRAACS).NOTE: Sodium nitroprusside solution is light-

sensitive. Store in and use from abrown bottle.

13. Calibration stock solution (100 mg NH 3/L):Dissolve 0.3144 g anhydrous ammoniumchloride, NH 4Cl, dried at 105 °C, in deionizedwater, and dilute to 1 L. Add 1 mL chloroformas a preservative.

EQUIPMENT:

1. Sampler:a. Prefilter (to remove particulate

interferences): 37-mm cellulose estermembrane filter (0.8-µm pore size)supported by stainless steel screen in twopiece cassette filter holder.

b. Sulfuric acid-treated silica gel samplingtubes. Glass tube with both endsunsealed and fire-polished, 6.0 cm longwith a 6-mm O.D. and a 4-mm I.D.containing two sections of 20/40 meshsulfuric acid-treated silica gel (200 mgfront/100 mg back) separated by a 2-mmportion of glass wool. Plugs of silylatedglass wool are placed at the ends of thetube. The pressure drop across the tubemust be <13 inches of water at a flow rateof 0.2 L/min (see APPENDIX). The glasstubes should be rinsed and dried withacetone before packing. The tubes arecapped with plastic caps. Tubes arecommercially available.

2. Personal sampling pump calibrated, 0.1 to0.2 L/min, with flexible tubing.

3. Technicon AutoAnalyzer Unit (AAII) (orTRAACS 800 equivalent) consisting of anautosampler, and analytical cartridge(AAII), proportioning pump, colorimeterequipped with 15-mm, 30-mm, or 50-mmtubular flow cell and 630- to 660-nmfilters, a data collection system, andrecorder.

4. pH Meter and pH electrode. 5. Plastic vials, 80-mL or 50-mL. 6. Polyethylene centrifuge tubes. 7. Magnetic stirrer and stirring bars. 8. Pipets: delivery type of convenient sizes. 9. Volumetric flasks: 1-L and 50-mL and

other convenient sizes for preparingstandard solutions.

10. Stopwatch.11. Manometer.




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SPECIAL PRECAUTIONS: Phenol is both corrosive and poisonous from ingestion, inhalation, orabsorption through the skin [10]. Avoid skin contact and inhalation of vapors. Sodium hydroxide, sulfuricacid, and sodium hypochlorite (bleach) are all corrosive. Avoid contact with skin or inhalation of vapors.Chloroform is believed to be carcinogenic [10], with reports of mutagenic and teratogenic effects inanimals. Handle in a hood and avoid skin contact. Sodium nitroprusside (sodium nitroferricyanide) ishighly toxic. Use extreme caution to avoid ingestion or inhalation of dust.

SAMPLING:

1. Calibrate each personal sampling pump with a representative sampler in line.2. Sample at an accurately known flow rate between 0.1 and 0.2 liter/minute for a total sample size

of 0.1 to 96 L.3. Cap the sampling tubes with plastic (not rubber) caps immediately after sampling.4. Pack securely for shipment.

SAMPLE PREPARATION:

5. Remove the plastic caps. Transfer the front and back sections of sulfuric acid-treated silica gelto separate 80-mL vials. Discard glass wool plugs. Analyze the two sections separately.NOTE: Firm tapping of the tube may be necessary to effect complete transfer of the sulfuric

acid-treated silica gel.6. Add 20 mL of ammonia-free deionized water to each vial. Cap and shake vigorously.

Desorption is complete in 45 minutes. Adjust the pH of each sample to 5.0 to 6.5 with sodiumhydroxide.NOTE: Analyses should be completed within one day after the ammonia is desorbed.

CALIBRATION AND QUALITY CONTROL:

7. Calibrate daily with at least six working standards over the range 0.05 to 1 µg/mL. Using thestock solution, prepare standards such as the following in 100-mL volumetric flasks (preparefresh daily):a. Add known amounts of calibration stock solution to deionized water in 100-mL volumetric

flasks and dilute to the mark. Prepare fresh daily.

NH3, µg/mL mL Stock Solution/100 mL

0.050.100.200.400.801.00

0.050.100.200.400.801.00

b. Analyze working standards together with samples and blanks (steps 9 through 12).c. The instrument automatically generates calibration graph (peak height versus concentration).

Sample concentrations will be printed out directly from this graph.8. Analyze three quality control blind spikes and three analyst spikes to ensure that the calibrating

graph is in control.




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MEASUREMENT:

9. For a working range of 0.05 to 1.0 µg NH 3/mL, set up the manifold as shown in Figure 1 forAAII and as shown in Figure 2 for TRAACS. Higher concentrations may be accommodated bysample dilution.

10. Allow both the colorimeter and the recorder to warm up for 30 minutes. Obtain a stablebaseline with all reagents, feeding deionized water through the sample line.

11. For normal conditions use a 30 or 40/hour 2:1 cam with a common wash for the AAII. For theTRAACS use a sampling rate between 90 and 120/hour with a 3:1, 4:1, or 5:1 sample/washratio.

12. Arrange ammonia standards in sampler in order of decreasing concentration of nitrogen. Complete loading of sampler tray with unknown samples. Begin analysis.

CALCULATIONS:

13. Read NH 3 concentration (µg/mL) found in sample front (W f) and back (W b) sorbent sectionsdirectly from the instrument printout.

14. Calculate the concentration (C) of NH 3 in the volume, V (L), of air sampled from the samplesolution concentrations, W f and Wb (µg/mL), multiplied by the appropriate solution volumes, V f

and Vb (mL):

REFERENCES:

[1] DataChem Laboratories report for NIOSH Seq. 7482-L (NIOSH/DPSE, unpublished, May 20,1992).

[2] NIOSH Manual of Analytical Methods, 2nd ed., Volume 5, S347, U.S. Department of Health,Education, and Welfare, Publ. (NIOSH) 79-141 (1979).

[3] Methods for Chemical Analysis of Water and Wastes, EPA-600/4-79-020 Revised March 1983,U.S. Environmental Protection Agency, Environmental Monitoring and Support Laboratory,Cincinnati, Ohio.

[4] Standard Methods for the Examination of Water and Wastewater, 16th ed., 1985, APHA,AWWA, WPCF.

[5] NIOSH Manual of Analytical Methods, 3rd ed., Method 6701, U.S. Department of Health,Education, and Welfare, Publ. (NIOSH) 84-100, February 1984.

[6] NIOSH Manual of Analytical Methods, 2nd ed., Volume 1, P&CAM 205, U.S. Department ofHealth, Education, and Welfare, Publ. (NIOSH) 77-157-A (1977).

[7] "Ammonia in Workplace Atmosphere" Method ID-164, Inorganic Methods Evaluation Branch,OSHA Analytical Laboratory, Salt Lake City, Utah.

[8] "Ammonia in Workplace Atmosphere" Method ID-188, Inorganic Methods Evaluation Branch,OSHA Analytical Laboratory, Salt Lake City, Utah, (April, 1988).

[9] The Merck Index, 11th Edition, 7206 Phenol, 2141 Chloroform, Merck & Co., Inc., Rahway, NJ(1989).

[10] NIOSH/OSHA Occupational Health Guidelines for Chemical Hazards, U.S. Department of Healthand Human Services Publ. (NIOSH) 81-123 (1981), available as GPO Stock #17-033-00337-8from Superintendent of Documents, Washington, D.C. 20402.

METHOD WRITTEN BY:

Norman K. Christensen, DataChem Laboratories, Salt Lake City, Utah.




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APPENDIX: PREPARATION OF SULFURIC ACID-TREATED SILICA GEL

1. Place 6 g of 20/40 mesh silica gel in 250-mL beaker.

2. Add 15 mL 0.4 N sulfuric acid to the beaker. Stir the mixture, and cover the beaker with a watchglass.

3. Heat the silica gel-acid mixture in a fume hood with a Bunsen burner to a very gentle boil. Evaporate approximately one-half of the liquid.

4. Place the covered beaker in a drying oven at 120 °C until the remainder of the water has beenevaporated.

5. The prepared acid-treated silica gel should flow freely and not adhere to the beaker. Store in silicagel in a desiccator until ready for use.




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NIOSH Manual of Analytical Methods (NMAM), Fifth Edition

AMMONIA by IC 6016

NH3 MW: 17.03 CAS: 7664-41-7 RTECS: BO0875000

METHOD: 6016, Issue 2 EVALUATION: FULL Issue 1: 15 May 1996 Issue 2: 3 March 2016 OSHA: 50 ppm NIOSH: 25 ppm; STEL 35 ppm

PROPERTIES: gas; MP -77.7 C; BP -33.4 C; VP 888 kPa (8.76 atm) @ 21.1 C; vapor density 0.6 (air = 1); explosive range 16 to 25% v/v in air

SYNONYMS: none

SAMPLING

SAMPLER: SOLID SORBENT TUBE (sulfuric acid-treated silica gel); a 0.8-µm MCE prefilter may be used to remove particulate interferences.

FLOW RATE: 0.1 - 0.5 L/min

VOL-MIN: 0.1 L @ 50 ppm -MAX: 96 L @ 50 ppm {1}

SHIPMENT: routine

SAMPLE STABILITY: at least 35 days @ 5 °C [2]

BLANKS: 2 to 10 field blanks per set

ACCURACY

RANGE STUDIED: 17 to 68 mg/m3 [1] (30-L samples)

BIAS: -2.4%

OVERALL PRECISION (𝑺𝑺�𝒓𝒓𝒓𝒓): 0.071 [1]

ACCURACY: ± 14.5%

MEASUREMENT

TECHNIQUE: ION CHROMATOGRAPHY, CONDUCTIVITY DETECTION

ANALYTE: ammonium ion (NH4+)

EXTRACTION ION: 10 mL deionized water

INJECTION VOLUME: 50 μL

ELUENT: 48 mM HCl/4 mM DAP-HCl/4 mM L-histidine-HCl; 1 mL/min alternate: 12 mM HCl/0.25 mM DAP-HCl/0.25 mM L-histidine-HCl; 1 mL/min

COLUMNS: cation separator; cation guard; cation micromembrane suppressor

CONDUCTIVITY SETTING: 30 μS full scale

CALIBRATION: standard solutions of NH4+ in deionized

water

RANGE: 8 to 100 µg/sample [3]

ESTIMATED LOD: 2 µg/sample [3]

PRECISION (𝑆𝑆��𝑟): 0.038 [2]

APPLICABILITY: The working range is 24 to 98 ppm (17 to 68 mg/m3) for a 30-L sample [1]. This method is applicable to STEL measurements when sampled at 0.2 L/min.

INTERFERENCES: Ethanolamines (monoethanolamine, isopropanolamine, and propanolamine) have retention times similar to NH4

+. The use of the alternate (weak) eluent will aid in separating these peaks.

OTHER METHODS: This method combines the sampling procedure of methods S347 [4] and 6015 [5] with an ion chromatographic analytical procedure similar to Method 6701 [6] and OSHA Method ID-188 [3].



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AMMONIA by IC: METHOD 6016, Issue 2, dated 3 March 2016 - Page 2 of 4


REAGENTS:

1. Water, deionized, filtered. 2. Sulfuric acid (H2SO4), 0.01 N:* Add 0.28 mL

conc. H2SO4 to 500 mL deionized water in 1-L volumetric flask. Dilute to 1 L with deionized water.

3. Hydrochloric acid (HCl), 1 N:* Add 82.5 mL conc. HCl to 500 mL deionized water in 1-L volumetric flask. Dilute to 1 L with deionized water.

4. 2,3-diaminopropionic acid monohydrochloride (DAP-HCl)

5. L-histidine monohydrochloride monohydrate (L-histidine-HCl)

6. Eluent (48 mM HCl/4 mM DAP-HCl/4 mM L-histidine-HCl): Place 0.560 g DAP-HCl and 0.840 g L-histidine-HCl in a 1-L volumetric flask. Add 48 mL of 1 N HCl, dilute to volume with deionized water. Prepare monthly.

7. Alternate eluent (12 mM HCl/0.25 mM DAP-HCl/0.25 mM L-histidine-HCl): Dilute 252 mL strong eluent and 36 mL 1 N HCl to 4 L with deionized water. Prepare fresh for each use.

8. Tetramethylammonium hydroxide (TMAOH), 25% in water.

9. Regenerant solution: Dilute 57.4 mL of 25% TMAOH to 4 L with deionized water.

10. Ammonia stock solution, 1000 µg/mL as NH3

(1059 µg/mL as NH4+): Dissolve 3.1409 g

ammonium chloride in deionized water. Dilute to 1 L. *See SPECIAL PRECAUTIONS.

EQUIPMENT:

1. Sampler: a. Prefilter: 37-mm mixed cellulose ester

membrane filter, 0.8-µm pore size, stainless steel or porous plastic screen in two piece cassette filter holder.

b. Sulfuric acid-treated silica gel, glass tube, unsealed and fire-polished, 6.0 cm long, 6-mm OD, 4-mm ID, containing two sections of 20/40 mesh sulfuric acid-treated silica gel (200 mg front/100 mg back) separated and held in place with plugs of silylated glass wool, and capped with plastic caps.

2. Personal sampling pump, 0.1 to 0.5 L/min, with flexible tubing.

3. Ion Chromatograph with conductivity detector, cation column and guard, and cation micromembrane suppressor (see Evaluation).

4. Syringes, 10-mL, polyethylene, Luer tip. 5. Centrifuge tubes, 15-mL, graduated, plastic

with screw caps. 6. Volumetric flasks, 10-, 50-, 100-mL, and 1-L. 7. Syringe filters, 13-mm, 0.8-µm, membrane

filter. 8. Micropipets, disposable tips. 9. Analytical balance (sensitivity to 0.01 mg).

SPECIAL PRECAUTIONS: Concentrated acids are corrosive to skin. Handle acid in a fume hood. Wear protective gloves.

SAMPLING:

1. Calibrate each personal sampling pump with a representative sampler in line. 2. Sample at an accurately known flow rate between 0.1 and 0.5 L/min for a total sample size of 0.1 to

96 L. 3. Cap the sampling tubes with plastic (not rubber) caps immediately after sampling. 4. Pack securely for shipment.



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SAMPLE PREPARATION:

5. Remove caps from sampling tubes. Transfer the front and back sections of sulfuric acid-treated silica gel to separate 15-mL graduated centrifuge tubes.

NOTE: Firm tapping of the tube may be necessary to effect complete transfer of the sulfuric acid-treated silica gel.

6. Add 10 mL of deionized water to each centrifuge tube. Cap and shake vigorously. Allow to stand 45 minutes with occasional shaking. (Desorption is complete in 45 minutes.) NOTE: Analyses should be completed within one day after the ammonia is desorbed.

7. Transfer samples to 10-mL syringes fitted with inline syringe filters for manual injection or transfer to autosampler vials.

CALIBRATION AND QUALITY CONTROL:

8. Calibrate daily with at least six working standards over the range of 1 to 110 µg NH3 per sample (about 0.11 to 12 µg/mL NH4

+). 9. Add known aliquots of ammonia stock solution to 0.01 N H2SO4 in 10-mL volumetric flasks.

NOTE: Prepare standards just before use. 10. Analyze working standards together with samples and blanks (steps 9 through 11). 11. Prepare calibration graph (peak height vs. µg NH3).

MEASUREMENT:

12. Set ion chromatograph to conditions given on page 6016-1, according to manufacturer’s instructions. 13. Inject 50-µL sample aliquot manually or with autosampler. For manual operation, inject 2 to 3 mL of

sample from filter/syringe to ensure complete rinse of sample loop. 14. Measure peak height.

NOTE: If peak height exceeds linear calibration range, dilute with 0.01 N H2SO4, reanalyze and apply the appropriate dilution factor in calculations.

CALCULATIONS:

15. Determine the mass, µg, of ammonia found in the sample front (Wf) and back (Wb) sorbent sections, and in the average media blank front (Bf) and back (Bb) sorbent sections.

16. Calculate concentration, C, of NH3 in the air volume sampled, V (L):

𝐶𝐶 =𝑊𝑊𝑓𝑓 + 𝑊𝑊𝑏𝑏 − 𝐵𝐵𝑓𝑓 − 𝐵𝐵𝑏𝑏

𝑉𝑉,𝑚𝑚𝑚𝑚/𝑚𝑚3

EVALUATION OF METHOD:

This method combines the sampling procedure of NIOSH Methods S347 [4] and 6015 [5] with the ion chromatographic analytical procedure of NIOSH Method 6701 [6] and OSHA Method ID-188 [3]. This method used HPIC-CS3 cation separator, HPIC-CG3 cation guard and CMMS-1 cation micromembrane suppressor. This method will serve as an alternate analytical procedure to the automated spectrophotometric procedure of NIOSH Method 6015 [5]. Although the methods from which this method is derived are fully evaluated methods, the combination of the sulfuric acid-treated silica gel sampler and IC analysis has not received a full evaluation, as such. During the development of the passive monitor method for ammonia (6701), sulfuric acid-treated silica gel tubes were used as one of the reference methods [6]. The silica gel samples with IC analysis showed good agreement with the other reference methods, bubbler collection with colorimetric analysis using Nessler’s Reagent, and bubbler collection with IC analysis.

A storage stability study compared the sulfuric acid-treated silica gel tube and sulfuric acid-treated carbon beads used in OSHA Method ID-188 [3]. When stored at room temperature for five days and then



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refrigerated for 21 days, silica gel samples had a mean recovery of 102 ± 3.8% (n = 8), while carbon beads had a mean recovery of 95 ± 1.6% (n = 8). The samples stored on carbon beads for 35 days showed significantly lower (although still acceptable) recovery compared to samples stored for 14 days: 103 ± 3.8% for silica gel (n = 12), and 108 ± 7.0% for carbon beads (n = 12) [2].

REFERENCES:

[1] NIOSH [1977]. Ammonia: Backup data report No. S347. Ten NIOSH analytical methods, set 6. SRI International Contract No. 210-76-0123. (NTIS PB-288629)

[2] Copenhafer RB, Dearden PA [1995]. User check of method 6015 for ammonia. Sequence 8321-J, K, L, M. Salt Lake City, UT: DataChem Labaratories. Unpublished.

[3] OSHA [1991]. Ammonia in workplace atmospheres - solid sorbent: Method ID-188. In: OSHA analytical methods manual, 2nd ed., Part 2, Inorganic substances. Salt Lake City, UT: U.S. Department of Labor, Occupational Safety and Health Administration.

[4] NIOSH [1979]. Ammonia: Method S347. In: Taylor DG, ed. NIOSH manual of analytical methods, 2nd ed., volume 5. Cincinnati, OH: U.S. Department of Health, Education and Welfare, Center for Disease Control, National Institute for Occupational Safety and Health, DHEW (NIOSH) Publication No. 79-141.

[5] NIOSH [1994]. Ammonia: Method 6015. In: Eller PM, Cassinelli ME, eds. NIOSH manual of analytical methods, 4th ed. Cincinnati, OH: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, DHHS(NIOSH) Publication No. 94-113 [www.cdc.gov/niosh/nmam].

[6] NIOSH [1984]. Ammonia: Method 6701. In: Eller PM, Cassinelli ME, eds. NIOSH manual of analytical methods, 3rd ed. Cincinnati, OH: U.S. Department of Health and Human Services, Centers for Disease Control, National Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 84-100.

METHOD WRITTEN BY:

Mary Ellen Cassinelli, NIOSH

Disclaimer: Mention of any company or product does not constitute endorsement by NIOSH. In addition, citations to websites external to NIOSH do not constitute NIOSH endorsement of the sponsoring organizations or their programs or products. Furthermore, NIOSH is not responsible for the content of these websites. All web addresses referenced in this document were accessible as of the publication date.

